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Powerline adapters with Sigma’s G.hn chips deliver UHD streams

Two G.hn powerline adapters arrived this week (at the Rider Research offices for review) from Sigma Designs, which makes G.hn chips. The adapters have an AC outlet built in so the user doesn’t lose a power outlet when they are plugged into the wall.

The adapters we received are “reference” units that equipment makers can use as a pattern when developing their own G.hn devices. A few equipment makers, such as Taiwan-based Prime Electronics and Satellitics (PES) with a set-top box, have already announced products with G.hn embedded. That means that once the STB or TV is plugged into the power socket, it’s automatically connected to the home network and to the Net via the home’s powerline. The power cord is the network connector.

The two questions we wanted to answer were 1) Can a non-techie consumer successfully install them without needing a technician? And are the speeds sufficient for streaming flicker-free UHD videos at the highest resolution available? Netflix and other OTT services use a technology called bit-rate adaption that automatically adjusts the resolution up or down to allow for continuous viewing at varying bandwidths. We wanted to see full UHD.

The answers to both questions turned out to be “yes.”

Sigma Designs cautioned us to ignore the speeds we measured because there is no reference point to compare against. It cannot be determined whether the speeds we measured are good or bad since there is nothing to compare — such as HomePlug adapters at the same electrical outlets. It would have been better to test in locations where we had also tested HomePlug.

We tested the G.hn adapters first in the office by copying files between two Windows 7 desktops; one connected directly to the switch and one connected to a G.hn adapter — as was the switch. The actual net speeds were 80-120 Mbps in one direction and 90 to 110 in the other. We don’t know what speeds two HomePlug devices might have shown.

The real test was at home, which involved streaming a number of Netflix’s UHD shows to a UHD TV via the G.hn powerline adapter. The TV was connected to a G.hn adapter as was a switch in another room. (Yes, homes are becoming tiny IT departments.)

We had no way at home to measure the actual net speed in that installation but there was no flicker or loss of resolution when the powerline adapters were used instead of the home’s Ethernet network. We switched the connection back and forth between the G.hn adapter and an Ethernet wireline network to see what resulted. There was no loss of resolution.

And, no technician was needed. It was plug and play.

There are a number of factors that impact data speed over powerline networks such as the wire’s condition and the number of electrical outlets. The adapters we tested are for use as reference designs by equipment makers and speeds may increase as designs improve. PCs, their ports and the networks they’re connected to must be capable of full gigabit throughput, which is not always the case, even in the large corporates.

Sigma Designs says that various tests, conducted by it, telcos, other G.hn chipmakers and manufacturers of G.hn devices, show that the powerline version of G.hn performs somewhat better than HomePlug over electrical lines with little interference and performs significantly better when a) there is a lot of interference on the powerline or b) when the total length of the home’s electrical wiring is quite large. Two telcos told Sigma Designs that they prefer G.hn powerline over HomePlug because it performs better at troublesome outlets. The thing about telcos (and cablecos) is that they can only ship products that work in all the homes in their footprint.

The thing about powerline adapters, whether based on G.hn or HomePlug technology, is that, in theory at least, every home is already wired so there’s at least one AC outlet, if not more, in every room, and often every wall in every home. That’s not true with coax, which only started being installed in homes with the advent of pay TV and is only in every room that has a TV. And only that in the US. Coax is considered much more reliable than powerline, but not as ubiquitous.

None of the WiFi adapters we have purchased so far, not even an 11ac model, covers every room in a 2,400 square feet home. The claims that WiFi proponents make are assuming no overlap of coverage between nearby residences and that there can be dedicated maximum bandwidth to a channel for a single device. That’s unlikely because it’s likely that there will be more than one device active at a time. As consumers start to put in multiple access points (APs) for better coverage they will likely cross-interfere or use different channels (although they can be coordinated).

The whole home Ethernet network that was installed some years ago could have been coax if the installer had known about MoCA then and if there had been MoCA adapters available at retail at that time, which they were not.

A few specialty WiFi chipmakers such as Quantenna and Celeno say their more powerful WiFi chips can match wireline in quality, reliability and speed. A few pay TV services (AT&T and DirecTV come to mind) are deploying WiFi adapters. Many pay TV services are said to be considering deploying devices with the more powerful WiFi chips for whole home networking, which DVRs use to connect multiple TVs.

None of those more powerful chips are yet available at retail so a consumer has these choices:
MoCA, which is currently available at retail. The newest version is MoCA 2.0; G.hn over coax, which is not yet available at retail; HomePlug AV or the faster AV2, which are readily available at retail; and  G.hn powerline, which is what we tested, although it is not yet available at retail, or Ethernet, like at the office, but which few homes have.

How much speed is needed? The coming of mass market priced UHD TVs will increase the need for faster speeds, especially since all UHD content that’s currently available can only be accessed at an OTT service. Netflix currently offers about 10-12 shows in UHD and Amazon has promised some this month but has not said whether they’ll be free on its Prime service or for purchase/rental.

Netflix says for its UHD shows, consumers need 12-15 Mbps per stream. Others have said 25-30 Mbps are needed per UHD stream. As a result, most homes with one UHD set need upwards of 100 Mbps. Most 11ac routers provide 100 Mbps, but WiFi is often not as reliable nor has the range as a wireline network.

What we don’t know yet is when will G.hn powerline adapters be available at retail? What will the retail pricing be? How well will they function with multiple streams of UHD videos and How do G.hn powerline adapters stack up against HomePlug AV2 in the same house?

What we do know is that for at least a year, most all UHD content will be available from an OTT service or from Sony and Samsung’s OTT download service. There will be no broadcasts in UHD from a pay TV service or from local TV stations. The UHD version of Blu-ray will not be available for about a year or so and even then consumers will have to purchase a new Blu-ray player that’s capable of playing UHD content.
Residences with UHD sets will need home networks (and broadband connections) that are capable of upwards of 100 Mbps for watching flicker-free videos anywhere in the home and at the highest resolution. G.hn chip and equipment makers have been focused on selling large quantities of G.hn products to telcos. However, there is a big market in retail, which HomePlug dominates.
There’s a need for makers of TVs, Blu-ray players and set-top boxes to build powerline networking into their products. By plugging the device into an AC outlet, the user gets both electrical power and a connection to the Web.

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